Background. The heterogeneity of schizophrenic and delusional
syndromes by age of onset has frequently been discussed.
Methods. The age distribution of symptoms and 5 year course
studied in a population-based
first-episode sample admitted to 10 psychiatric hospitals before the age
60 (N=232) and in a
clinical sample without age limit of consecutive first admissions to a
hospital (N=1109), both samples with broadly diagnosed schizophrenia.
Results. Early-onset patients, particularly men, presented
more non-specific symptoms and higher
PSE-CATEGO total scores than late-onset patients. In men, symptom severity
increasing age of onset. In women, it remained stable except for an
increase of negative symptoms
with late-onset. Only a few symptoms changed markedly with age:
disorganization decreased, while
paranoid and systematic delusions increased steeply across the whole age
of onset range. Pronounced
age- and sex-differences emerged in illness behaviour, socially negative
behaviour and substance
abuse. Within the group of late-onset psychoses there were continuous transitions
profiles and no discrimination between schizophrenia and paranoid
psychosis or late paraphrenia.
The main determinant of social course was onset level of social
development. Early-onset patients
did not improve in social status, while late-onset patients, prior
to retirement, suffered considerable decline in social status.
Conclusions. Gender differences in age at onset and in age
trends in symptom severity support the
hypothesis of a mild protective effect of oestrogen. Social course results
from an interplay between
biological factors (age at onset and functional impairment) and development
factors (level of social development at onset and illness behaviour).